Can I set the start point of a bezier curve?
The thumb rule is that basically, for a closed spline, the last segment created upon closing a curve is will contain the first vertex of the curve spline.
So if you want to make a certain vertex the first one, then delete the segment immediately before or after it to make that vertex the starting point. Then close that spline again.
As far as I know there is no easy way to determine which of the gaping vertex will actually become the first one. And on 2D curves, you can't tell them apart easily because there are no normal arrow indicators to guide you.
If you don't like the outcome though, you can always open the curve again, and call Switch Direction operator, either from the Search menu, Right Click context menu, or Segments &gt; Switch Direction, reverse the result as desired then close the spline again.

For 2.8+ you can also activate the addon Curve Tools from the preferences, and under the Edit tab of the 3D View sidebar under Utilities &gt; Set First Point allows setting an arbitrary point as first for selected splines.